lily/slur-configuration.cc

   1 /*
   2   slur-configuration.cc --  implement Slur_configuration
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2004 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7
   8 */
   9
  10 #include <math.h>
  11
  12 #include "stem.hh"
  13 #include "warn.hh"
  14 #include "misc.hh"
  15 #include "item.hh"
  16 #include "group-interface.hh"
  17 #include "slur.hh"
  18 #include "slur-scoring.hh"
  19 #include "slur-configuration.hh"
  20 #include "spanner.hh"
  21 #include "staff-symbol-referencer.hh"
  22 #include "libc-extension.hh"
  23
  24 Bezier
  25 avoid_staff_line (Slur_score_state const &state,
  26                   Bezier bez)
  27 {
  28   Offset horiz (1,0);
  29   Array<Real> ts = bez.solve_derivative (horiz);
  30
  31   /* TODO: handle case of broken slur.  */
  32   if (!ts.is_empty ()
  33       && (state.extremes_[LEFT].staff_ == state.extremes_[RIGHT].staff_)
  34       && state.extremes_[LEFT].staff_ && state.extremes_[RIGHT].staff_)
  35     {
  36       Real y = bez.curve_point (ts[0])[Y_AXIS];
  37
  38       Grob *staff = state.extremes_[LEFT].staff_;
  39
  40       Real p = 2 * (y - staff->relative_coordinate (state.common_[Y_AXIS], Y_AXIS))
  41         / state.staff_space_;
  42
  43       Real distance = fabs (my_round (p) - p);  //  in halfspaces
  44       if (distance < 4 * state.thickness_
  45           && (int) fabs (my_round (p))
  46           <= 2 * Staff_symbol_referencer::staff_radius (staff) + 0.1
  47           && (int (fabs (my_round (p))) % 2
  48               != Staff_symbol_referencer::line_count (staff) % 2))
  49         {
  50           Direction resolution_dir =
  51          (distance ?  state.dir_ : Direction (sign (p - my_round (p))));
  52
  53           // TODO: parameter
  54           Real newp = my_round (p) + resolution_dir
  55             * 5 * state.thickness_;
  56
  57           Real dy = (newp - p) * state.staff_space_ / 2.0;
  58
  59           bez.control_[1][Y_AXIS] += dy;
  60           bez.control_[2][Y_AXIS] += dy;
  61         }
  62     }
  63   return bez;
  64 }
  65
  66 Real
  67 fit_factor (Offset dz_unit, Offset dz_perp,
  68             Bezier curve, Direction d,  Array<Offset> const &avoid)
  69 {
  70   Real fit_factor = 0.0;
  71   Offset x0 = curve.control_[0];
  72   curve.translate (-x0);
  73   curve.rotate (-dz_unit.arg ());
  74   curve.scale (1, d);
  75
  76   Interval curve_xext;
  77   curve_xext.add_point (curve.control_[0][X_AXIS]);
  78   curve_xext.add_point (curve.control_[3][X_AXIS]);
  79
  80   for (int i = 0; i < avoid.size (); i++)
  81     {
  82       Offset z = (avoid[i] - x0) ;
  83       Offset p (dot_product (z, dz_unit),
  84                 d* dot_product (z, dz_perp));
  85       if (!curve_xext.contains (p[X_AXIS]))
  86         continue;
  87
  88       Real y = curve.get_other_coordinate (X_AXIS, p[X_AXIS]);
  89       if (y)
  90         {
  91           fit_factor = fit_factor >? (p[Y_AXIS] / y);
  92         }
  93     }
  94   return fit_factor;
  95 }
  96
  97
  98 Bezier
  99 get_bezier (Slur_score_state const &state,
 100             Drul_array<Offset> attachments,
 101             Real r_0, Real h_inf)
 102 {
 103   Link_array<Grob> encompasses = state.columns_;
 104
 105   Array<Offset> avoid;
 106   for (int i = 0; i < encompasses.size (); i++)
 107     {
 108       if (state.extremes_[LEFT].note_column_ == encompasses[i]
 109           || state.extremes_[RIGHT].note_column_ == encompasses[i])
 110         continue;
 111
 112       Encompass_info inf (state.get_encompass_info (encompasses[i]));
 113       Real y = state.dir_ * ((state.dir_ * inf.head_) >? (state.dir_ *inf.stem_));
 114
 115       avoid.push (Offset (inf.x_,  y + state.dir_ * state.parameters_.free_head_distance_));
 116     }
 117
 118   Link_array<Grob> extra_encompasses
 119     = Pointer_group_interface__extract_grobs (state.slur_, (Grob *)0, "encompass-objects");
 120   for (int i = 0;  i < extra_encompasses.size (); i++)
 121     if (Slur::has_interface (extra_encompasses[i]))
 122       {
 123         Grob * small_slur = extra_encompasses[i];
 124         Bezier b = Slur::get_curve (small_slur);
 125
 126         Offset z = b.curve_point (0.5);
 127         z += Offset (small_slur->relative_coordinate (state.common_[X_AXIS], X_AXIS),
 128                      small_slur->relative_coordinate (state.common_[Y_AXIS], Y_AXIS));
 129
 130         z[Y_AXIS] += state.dir_ * state.parameters_.free_slur_distance_;
 131         avoid.push (z);
 132       }
 133
 134   Offset dz = attachments[RIGHT]- attachments[LEFT];;
 135   Offset dz_unit = dz;
 136   dz_unit *= 1 / dz.length ();
 137   Offset dz_perp = dz_unit * Offset (0, 1);
 138
 139   Real indent, height;
 140   get_slur_indent_height (&indent, &height, dz.length (), h_inf, r_0);
 141
 142
 143   Real len = dz.length ();
 144
 145   /* This condition,
 146
 147      len^2 > 4h^2 +  3 (i + 1/3len)^2  - 1/3 len^2
 148
 149      is equivalent to:
 150
 151      |bez' (0)| < | bez' (.5)|
 152
 153      when (control2 - control1) has the same direction as
 154     (control3 - control0).  */
 155
 156
 157
 158   Real max_indent = len / 3.1;
 159   indent = indent <? max_indent;
 160
 161   Real a1 = sqr (len) / 3.0;
 162   Real a2 = 0.75 * sqr (indent + len / 3.0);
 163   Real max_h = a1 - a2;
 164
 165
 166   if (max_h < 0)
 167     {
 168       programming_error ("Slur indent too small.");
 169       max_h = len / 3.0 ;
 170     }
 171   else
 172     {
 173       max_h = sqrt (max_h);
 174     }
 175
 176   Real excentricity = robust_scm2double (state.slur_->get_property ("excentricity"), 0);
 177
 178   Real x1 = (excentricity + indent);
 179   Real x2 = (excentricity - indent);
 180
 181   Bezier curve;
 182   curve.control_[0] = attachments[LEFT];
 183   curve.control_[1] = attachments[LEFT] + dz_perp * height * state.dir_
 184     + dz_unit * x1;
 185   curve.control_[2] = attachments[RIGHT] + dz_perp * height * state.dir_
 186     + dz_unit * x2;
 187   curve.control_[3] = attachments[RIGHT];
 188
 189   Real ff = fit_factor (dz_unit, dz_perp, curve, state.dir_, avoid);
 190
 191   height = height >? ((height * ff) <? max_h);
 192
 193   curve.control_[0] = attachments[LEFT];
 194   curve.control_[1] = attachments[LEFT] + dz_perp * height * state.dir_
 195     + dz_unit * x1;
 196   curve.control_[2] = attachments[RIGHT] + dz_perp * height * state.dir_
 197     + dz_unit * x2;
 198   curve.control_[3] = attachments[RIGHT];
 199
 200   return curve;
 201 }
 202
 203 Slur_configuration::Slur_configuration()
 204 {
 205   score_ = 0.0;
 206 };
 207
 208 void
 209 Slur_configuration::generate_curve (Slur_score_state const &state,
 210                                     Real r_0, Real h_inf )
 211 {
 212   Bezier bez = get_bezier (state,
 213                            attachment_, r_0, h_inf);
 214
 215   bez = avoid_staff_line (state, bez);
 216   attachment_[LEFT] = bez.control_[0];
 217   attachment_[RIGHT] = bez.control_[3];
 218   curve_ = bez;
 219 }
 220
 221 void
 222 Slur_configuration::score_encompass (Slur_score_state const &state)
 223 {
 224   Bezier const &bez (curve_);
 225   Real demerit = 0.0;
 226
 227   /*
 228     Distances for heads that are between slur and line between
 229     attachment points.
 230   */
 231   Array<Real> convex_head_distances;
 232   Array<Real> edge_distances;
 233   for (int j = 0; j < state.encompass_infos_.size (); j++)
 234     {
 235       Real x = state.encompass_infos_[j].x_;
 236
 237       bool l_edge = j==0;
 238       bool r_edge = j==state.encompass_infos_.size ()-1;
 239       bool edge =  l_edge || r_edge;
 240
 241
 242       if (edge)
 243         {
 244           edge_distances.push (fabs (attachment_[l_edge ? LEFT : RIGHT][Y_AXIS]
 245                                      - state.encompass_infos_[j].get_point (state.dir_)));
 246         }
 247
 248
 249       if (! (x < attachment_[RIGHT][X_AXIS]
 250              && x > attachment_[LEFT][X_AXIS]))
 251         continue;
 252
 253       Real y = bez.get_other_coordinate (X_AXIS, x);
 254       if (!edge)
 255         {
 256           Real head_dy = (y - state.encompass_infos_[j].head_);
 257           if (state.dir_ * head_dy < 0)
 258             {
 259               demerit += state.parameters_.head_encompass_penalty_;
 260               convex_head_distances.push (0.0);
 261             }
 262           else
 263             {
 264               Real hd = (head_dy)
 265                 ? (1 / fabs (head_dy) - 1 / state.parameters_.free_head_distance_)
 266                 : state.parameters_.head_encompass_penalty_;
 267               hd = (hd >? 0)<? state.parameters_.head_encompass_penalty_;
 268
 269               demerit += hd;
 270             }
 271
 272           Real line_y = linear_interpolate (x,
 273                                             attachment_[RIGHT][X_AXIS],
 274                                             attachment_[LEFT][X_AXIS],
 275                                             attachment_[RIGHT][Y_AXIS],
 276                                             attachment_[LEFT][Y_AXIS]);
 277
 278           if ( 1 ) // state.dir_ * state.encompass_infos_[j].get_point (state.dir_) > state.dir_ *line_y )
 279             {
 280
 281               Real closest =
 282                 state.dir_ * (state.dir_ * state.encompass_infos_[j].get_point (state.dir_)
 283                               >? state.dir_ *line_y
 284                               );
 285               Real d = fabs (closest - y);
 286
 287               convex_head_distances.push (d);
 288             }
 289         }
 290
 291
 292
 293       if (state.dir_ * (y - state.encompass_infos_[j].stem_) < 0)
 294         {
 295           Real stem_dem =state.parameters_.stem_encompass_penalty_ ;
 296           if ((l_edge && state.dir_ == UP)
 297               || (r_edge && state.dir_ == DOWN))
 298             stem_dem /= 5;
 299
 300           demerit +=  stem_dem;
 301         }
 302       else if (!edge)
 303         {
 304           Interval ext;
 305           ext.add_point (state.encompass_infos_[j].stem_);
 306           ext.add_point (state.encompass_infos_[j].head_);
 307
 308           // ?
 309           demerit += -state.parameters_.closeness_factor_
 310             * (state.dir_
 311                * (y - (ext[state.dir_] + state.dir_ * state.parameters_.free_head_distance_))
 312                <? 0)
 313             / state.encompass_infos_.size ();
 314         }
 315     }
 316
 317   Real variance_penalty = 0.0;
 318
 319   if (convex_head_distances.size ())
 320     {
 321       Real avg_distance = 0.0;
 322       Real min_dist = infinity_f;
 323       for (int j = 0; j < convex_head_distances.size (); j++)
 324         {
 325           min_dist = min_dist <? convex_head_distances[j];
 326           avg_distance += convex_head_distances[j];
 327         }
 328
 329       /*
 330         For slurs over 3 or 4 heads, the average distance is not a
 331         good normalizer.
 332       */
 333       int n =  convex_head_distances.size ();
 334       if (convex_head_distances.size () <= 2)
 335         {
 336           //          Real min_edge_dist = 1e6;
 337           for (int j = 0; j < edge_distances.size (); j++)
 338             {
 339               avg_distance += edge_distances[j];
 340               n++;
 341             }
 342
 343         }
 344
 345       /*
 346         TODO: maybe it's better to use (avgdist - mindist)*factor
 347         as penalty.
 348       */
 349       avg_distance /= n;
 350       variance_penalty = state.parameters_.head_slur_distance_max_ratio_;
 351       if (min_dist > 0.0)
 352         variance_penalty = ((avg_distance / (min_dist  +state.parameters_.free_head_distance_)) - 1.0)
 353           <? variance_penalty;
 354
 355       variance_penalty *= state.parameters_.head_slur_distance_factor_;
 356     }
 357 #if DEBUG_SLUR_SCORING
 358   score_card_ += to_string ("C%.2f", demerit);
 359   score_card_ += to_string ("D%.2f", variance_penalty);
 360 #endif
 361
 362   score_ += demerit + variance_penalty;
 363 }
 364
 365 void
 366 Slur_configuration::score_extra_encompass (Slur_score_state const &state)
 367 {
 368   Real demerit = 0.0;
 369   for (int j = 0; j < state.extra_encompass_infos_.size (); j++)
 370     {
 371       Drul_array<Offset> attachment = attachment_;
 372       Interval slur_wid (attachment[LEFT][X_AXIS], attachment[RIGHT][X_AXIS]);
 373
 374       /*
 375         to prevent numerical inaccuracies in
 376         Bezier::get_other_coordinate ().
 377       */
 378       Direction d = LEFT;
 379       bool found = false;
 380       Real y = 0.0;
 381
 382       do
 383         {
 384           /*
 385             We need to check for the bound explicitly, since the
 386             slur-ending can be almost vertical, making the Y
 387             coordinate a bad approximation of the object-slur
 388             distance.
 389           */
 390           Item * as_item =  dynamic_cast<Item*> (state.extra_encompass_infos_[j].grob_);
 391           if ((as_item
 392                && as_item->get_column ()
 393                == state.extremes_[d] .bound_->get_column ())
 394               || state.extra_encompass_infos_[j].extents_[X_AXIS].contains (attachment[d][X_AXIS]))
 395             {
 396               y = attachment[d][Y_AXIS];
 397               found = true;
 398             }
 399         }
 400       while (flip (&d) != LEFT);
 401
 402       if (!found)
 403         {
 404           Real x = state.extra_encompass_infos_[j].extents_[X_AXIS]
 405             .linear_combination (state.extra_encompass_infos_[j].idx_);
 406
 407           if (!slur_wid.contains (x))
 408             continue;
 409
 410           y = curve_.get_other_coordinate (X_AXIS, x);
 411         }
 412
 413       Real dist = state.extra_encompass_infos_[j].extents_[Y_AXIS].distance (y);
 414       demerit +=
 415         fabs (0 >? (state.parameters_.extra_encompass_free_distance_ - dist)) /
 416         state.parameters_.extra_encompass_free_distance_
 417         * state.extra_encompass_infos_[j].penalty_;
 418     }
 419 #if DEBUG_SLUR_SCORING
 420   score_card_ += to_string ("X%.2f", demerit);
 421 #endif
 422   score_ += demerit;
 423 }
 424
 425 void
 426 Slur_configuration::score_edges (Slur_score_state const &state)
 427 {
 428   Direction d = LEFT;
 429   Offset dz = attachment_[RIGHT]
 430     - attachment_[LEFT];
 431   Real slope = dz[Y_AXIS] / dz[X_AXIS];
 432   do
 433     {
 434       Real y = attachment_[d][Y_AXIS];
 435       Real dy = fabs (y - state.base_attachments_[d][Y_AXIS]);
 436
 437       Real factor = state.parameters_.edge_attraction_factor_;
 438       Real demerit = factor * dy;
 439       if (state.extremes_[d].stem_
 440           && state.extremes_[d].stem_dir_ == state.dir_
 441           && !Stem::get_beaming (state.extremes_[d].stem_, -d)
 442           )
 443         demerit /= 5;
 444
 445       demerit *= exp (state.dir_ * d * slope
 446                       * state.parameters_.edge_slope_exponent_ );
 447
 448       score_ += demerit;
 449 #if DEBUG_SLUR_SCORING
 450       score_card_ += to_string ("E%.2f", demerit);
 451 #endif
 452     }
 453   while (flip (&d) != LEFT);
 454 }
 455
 456 void
 457 Slur_configuration ::score_slopes (Slur_score_state const &state)
 458 {
 459   Real dy = state.musical_dy_;
 460   Offset slur_dz = attachment_[RIGHT] - attachment_[LEFT];
 461   Real slur_dy = slur_dz[Y_AXIS];
 462   Real demerit = 0.0;
 463
 464   demerit += ((fabs (slur_dy / slur_dz[X_AXIS])
 465                - state.parameters_.max_slope_) >? 0)
 466     * state.parameters_.max_slope_factor_;
 467
 468   /* 0.2: account for staffline offset. */
 469   Real max_dy = (fabs (dy) + 0.2);
 470   if (state.edge_has_beams_)
 471     max_dy += 1.0;
 472
 473   if (!state.is_broken_)
 474     demerit += state.parameters_.steeper_slope_factor_
 475       * ((fabs (slur_dy) -max_dy) >? 0);
 476
 477   demerit += ((fabs (slur_dy/slur_dz[X_AXIS])
 478                - state.parameters_.max_slope_) >? 0)
 479     * state.parameters_.max_slope_factor_;
 480
 481   if (sign (dy) == 0
 482       && sign (slur_dy) != 0
 483       && !state.is_broken_)
 484     demerit += state.parameters_.non_horizontal_penalty_;
 485
 486   if (sign (dy)
 487       && !state.is_broken_
 488       && sign (slur_dy)
 489       && sign (slur_dy) != sign (dy))
 490     demerit += state.edge_has_beams_
 491       ? state.parameters_.same_slope_penalty_ / 10
 492       : state.parameters_.same_slope_penalty_;
 493
 494 #if DEBUG_SLUR_SCORING
 495   score_card_ += to_string ("S%.2f", demerit);
 496 #endif
 497   score_ += demerit;
 498 }
 499
 500
 501 void
 502 Slur_configuration::score (Slur_score_state const &state)
 503 {
 504   score_extra_encompass (state);
 505   score_slopes  (state);
 506   score_edges (state);
 507   score_encompass (state);
 508 }